Street sweeping machine



March 13, 1962 RF. SCHMIDT ETAL 3,024,485

STREET SWEEPING MACHINE 3 Sheets-Sheet 1 Filed Oct. 30, 1959 M y d w x INVENTOR EOBEPT F SCH/P1707 f/E/VEY 4. [.'lOEC/( W BY ATTORNEY March 13, 1962 R. F. SCHMIDT ETAL 3,024,485

STREET SWEEPING MACHINE 3 Sheets-Sheet 2 Filed Oct. 50, 1959 s 5 E7 0 m M; a p, i v we 3 5 BY 7 W M W March 13, 1962 R. F. SCHMIDT ETAL 3,024,485

STREET SWEEPING MACHINE Filed 001; 30, 1959 3 Sheets-Sheet 3 INVENTORS P0559? E saw/war A/AWPY A. ALI/056KB? WMMMW ATTORNEYS United States Patent U 3,024,485 STREET SWEEPING MACHINE Robert F. Schmidt, Elgin, and Henry A. Leidecker, Wheaton, Ill., assignors to Elgin Sweeper Company, Elgin, Ill., a corporation of Delaware Filed Oct. 31), 1959, Ser. No. 849,824 3 Claims. (Cl. 15--84) The present invention relates to improvements in a sweeping machine and particularly to improvements in a mechanism for conveying dirt and foreign materials upwardly from a rotary street sweeping broom into a hopper of the machine.

In a sweeping machine of the general type with which the features of the present invention are employed, a cylindrically shaped rotary main broom is mounted on the machine and driven in rotation to sweep the dirt and foreign materials from a street surface forwardly. A side broom is driven in rotation to sweep dirt inwardly. Ahead of the main broom is an upwardly extending dirt conveyer to carry the materials swept by the main broom into a hopper on the machine, with a hopper being dumped when filled or at the end of a sweeping operation.

An object of the present invention is to provide an improved sweeping machine and an improved conveyor mechanism therefore which is extremely rigid and stable for a more uniform and reliable conveying operation.

Another object of the invention is to provide an improved conveyer for a street sweeping machine wherein the belt may be changed or repaired with a minimum amount of effort and without major disassembly of the machine.

A further object of the invention is to provide a conveyor for a street sweeping machine enabling the use of shorter self centering rolls of a relatively large diameter and utilizing a spliced belt.

A further object of the invention is to provide an improved conveyer for a street sweeping machine with a frame that is welded as an integral single piece unit giving rigid support to the rolls.

A still further object of the invention is to provide an improved elevating conveyer for a street sweeping machine with deflectors to keep the material centered on the conveyer and with improved elevating mechanism for raising the conveyer when the machine is not in operation.

A still further object of the invention is to provide an improved drive for the elevating conveyer of a street sweeping machine.

Other objects and advantages will become more apparem with the teaching of the principles of the invention in connection with the disclosure of the preferred embodiment thereof in the specification, claims and drawings, in which:

FIGURE 1 is a perspective view of a street sweeping machine of the type embodying the principles of the present invention;

FIGURE 2 is a side elevational view, shown partially in section and with parts removed to illustrate the elevating conveyer mechanism;

FIGURE 3 is a plan view of the frame for the conveyer;

FIGURE 4 is a sideelevational view of the-conveyer frame of FIGURE 3;

FIGURE 5 is an end elevational view of a side member of the conveyer frame;

FIGURE 6 is a fragmentary perspective view illustrating a drive mechanism for the conveyer;

- FiGURE 7 is an elevational view showing one of the rolls for the conveyer belt;

FIGURE 8 is a fragmentary perspective view illustrating the lower end of the conveyer assembly with the portions broken away for purposes of illustration;

FIGURE 9 is a vertical sectional view takenthrough the side, of the conveyer and illustrating one of the conveyer elevating cylinders with parts broken away for illustration;

FIGURE 10 is a diagrammatic view of the hydraulic circuit and mechanism for elevating the conveyer; and,

FIGURE 11 is a fragmentary vertical sectional view of one side of the conveyer taken substantially along line XIXI of FIGURE 2.

As shown on the drawings:

FIGURE 1 illustrates a street sweeping machine including a main frame and housing shown generally at 1 1 ambulantly supported on front drive wheels 12 and a rear steering wheel 13. The vehicle is propelled and the brooms are driven by an engine 14 controlled by an operator seated in the vehicle at 15. The machine sweeps a surface 16 ofa street or the like and employs a rotary generally cylindrical main broom 17 which is rotatably supported at its ends and driven in rotation. The dirt and foreign materials swept from the street surface are thrown forwardly and received by a conveyer 18 and carried upwardly to a hopper 20 which is closed by a controlled door so as to be able to dump the dirt at the end of a run or when the hopper is filled. Side shoes 19 are provided at the ends of the main broom to retain dirt in the path thereof and to prevent streaking. A center dirt deflector and a dirt deflector under the conveyer are provided and the deflector under the conveyer can be removed if necessary during the leaf season and controls gravel stones and the like from being thrown clear of the sweeping path. A side broom 21 is located ahead of the main broom at the side of the machine and is suitably driven through the roller chains and sprockets from the engine. Further details of the main broom and side broom are disclosed in our copending applications U.S. Serial No. 846,165, filed Oct. 13, 1959, and US. Serial No. 842,342, filed Sept. 25, 1959.

As illustrated in FIGURES 1 and 2, the main broom 17 is rotatabiy mounted on a horizontal support shaft 22 carried at the lower ends of arms 23 which are pivotally mounted at 25, and the main broom is lifted and its sweeping pressure is controlled by a hydraulic cylinder 24. The main broom is suitably driven from the engine 14-and the engine connects through a (inferential 26 to drive the drive Wheels by sprockets and a chain shown diagrammatically at 27.

The conveyer 18 extends upwardly from in front of the main broom 17 to the hopper 20. The conveyer includes a conveyer belt 28 which is formed in an endless loop and is supported on rolls 29 and 30. The rolls are substantially identical in construction and therefore only the roll 3%) will be described as illustrated in FIG- URE 7. The roll 39 has shaft ends 31 and 32 extending from its end for rotatably supporting it onsuitable hearings. The center of the roll is raised or crowned as illustrated at 33 to insure that the belt will remain, centered and will automatically track on the rolls. The rolls are rigidly supported in a belt frame 34 and are held in horizontal parallel relationship and are of a substantially large diameter. This increases the operating life of the belt and insures reliable operation. The belt is formed with ends 3006 and'30b, FIGURE 8, which are connected by a mechanical splice 35. The splice or fastener 35 is removable permitting rapid disassembly as well as eco: nomical field repair. The belt is formed of a heavy mate-: rial such as two-ply rubber and may have integrally molded cleats, not shown, to deliver the material picked up by the main broom to the hopper. With the arrangement illustrated, disassembly of the mechanism is, not required for repairing or changing the belt and eco+ nomical and rapid repair is possibleteven inthe field.

The belt is driven by a hydraulic motor36,.F IG URESa2 and 6, suitably mounted such as at the side of the belt frame 34. The hydraulic motor drives a sprocket 37 carrying a drive chain 38 passing over a sprocket 39 mounted on a shaft 40 connected to the upper roll 29; Overload protection in case the conveyer becomes clogged is afforded by a relief valve in the hydraulic system such as may be incorporated in a control valve 75, FIGURE 10. The conveyer belt drive may be easily controlled and may be engaged, disengaged and reversed in direction by a control valve regulating the flow of hydraulic fluid to the motor 36.

Within the belt 28 and mounted on the belt frame 34 there may be provided a roll scraper 41 which is adjustably supported to engage the lower roll 30 for keeping it clean of foreign materials and for preventing material from accumulating on the roll.

As illustrated primarily in FIGURES 2 through 6, 8 and 11, the conveyer frame 34- is located largely within the belt and extends between the two rolls 29 and 30. The frame includes frame side members 42 and 43, FIGURE 3, and cross frame members 44 and 45 connected at their ends to the side frame members. Diagonal frame members 4-6 and 47 are connected at their ends to the side frame members and longitudinal frame members 48, 49, t) and 51 are secured to the cross frame members 44 and 45 and provide supports for guiding the upper run of the belt 28, as illustrated in FIGURE 8. The side frame members, the cross frame members, the diagonal frame members and the longitudinal frame members are interwelded to provide a rigid non-yielding frame.

The lower roll 30 is suitably rotatably journalled in bearings mounted at the lower ends of the side frame members 42 and 43, as illustrated by the end bearing 52 which is secured to the side frame member 42, FIGURE 8. The upper roll 29 is similarly suitably rotatably supported in bearings and these bearings may be adjustably carried at the upper ends of the side frame members 42 and 43 such as by bearing mounts 53, FIGURE 6, mounted on the side frame member 42. The side frame members are basically U-shaped in section, as illustrated in FIGURE 5.

As illustrated in FIGURE 11, the dirt is centered on the belt 28 by deflectors 56 which are formed of an abrasive resistant rubber. The deflectors are supported on brackets 54 mounted on the side frame members with an upper part 55 to which the deflectors 56 are connected. A deflector is provided for each side of the belt 28.

The conveyer frame 34 is pivotally supported on the main frame 11 of the machine on trunnions 57 and 58, FIGURE 3. The trunnions are carried on plates which are mounted on the side frame members, as shown somewhat schematically in the drawings. The trunnions are mounted in bearings, such as illustrated at 59 in FIGURE 11 supported on brackets 60 mounted on the machine frame 11.

The conveyer is elevated by a mechanism illustrated particularly in FIGURES 2 and 9 including conveyer elevators or lifters 61 at each side of the belt frame. The lifters act on side brackets 62 and 63, FIGURE 3, which extend rigidly outwardly from the belt frame side members 42 and 43. The lifters include a cylinder 64 with a piston 65 slidable therein, FIGURE 9, and a pressurized hydraulic fluid is directed to the cylinder through a fitting 66. The piston is suitably connected to a bracket 67 on the machine frame 11. The piston has an extension rod 68 of smaller diameter which extends up through a hole 69 in the bracket 62 and the upper end of the piston at the base of the rod engages the lower surface of the bracket 62 to apply an upward lifting force.

The hydraulic circuit for controlling the hydraulic fluid to operate the various hydraulic devices is illustrated diagrammatically in FIGURE 10. The hydraulic fluid is delivered by pump 70 having an intake line 71 receiving fluid from the reservoir 72 provided with a, breather 73. The pressurized fluid is delivered through a line '74 to a main control valve 75. The control valve is provided with a suitable control connection and delivers fluid to the hydraulic motor 36 for driving the conveyer belt. The arrows on the lines connecting from the valve 75 to the motor 36 show the direction of fluid flow when the conveyer is driven forwardly.

Also operated from the main control valve 75 is a hydraulic mechanism for controlling the door of the hopper on the machine. Delivery and return lines 76 and 77 connect to the valve 75 and connect to a hopper pilot operated check valve 78 and lead to a hopper door operating hydraulic cylinder 79.

The conveyer is elevated by a fluid directed from the main control valve 75 through a delivery line 80 through a return flow preventing check valve 82. A manually opened or closed valve 82 is connected in a line 83 by-passing the check valve 81 and the valve 82 can be closed when the conveyer is to be held elevated.

At the ends of the main broom 17 are side shoes 19 comprising vertical plates with runners 84 at their lower edge for engaging the surface being swept. The runners are formed of abrasion resistant rubber and the side shoes are full floating with the adjustments provided in all directions to insure uniform contact with the street conditions. An adjustable spring 91 connects between the front of the shoe and an arm 86 to insure uniform wear of the abrasion resistant runners.

The shoes are supported on the arms 86 pivotally mounted in a center location 87 at the lower end of the conveyer belt frame. The shoe is pivotally connected at 88 to the arm 86. The shoe is provided with a slot so that it can be lifted along the end of the main broom 17 past the broom shaft 22. When the conveyor frame is lifted, the shoe supporting arm 86 will pivot counterclockwise (FIGURE 2) until its end hits a pin 89 on the conveyer frame after which the pivotal movement of the arm 86 will be stopped and the shoe will be lifted with the conveyer. A tension spring 91 connects between the forward end of the shoe 84 and the arm 86 so that the front end of the shoe will not drop down by the shoe pivoting forwardly when it is lifted. Thus the conveyer has a limited up and down movement while the shoe is permitted to ride on the surface being swept but after a predetermined amount of elevation the shoe will be lifted with the conveyer. The conveyer elevators or lifters thus perform a dual function and lift the conveyer and the side shoes.

A center dirt deflector, not shown is located under the machine. A dirt deflector 90, FIGURE 2, is located under the conveyer structure. This can be removed if necessary during the leaf season and functions to control gravel, stones, etc. from being thrown clear of the sweeping path.

In operation the driver of the machine lowers the conveyer into the position shown in FIGURES 1 and 2 and drives the machine forwardly with the main broom 17 and the side broom 21 operating to clear the street surface and with the dirt being carried upwardly into the hopper 20 on the machine by the conveyer assembly 18. The conveyer frame 34 maintains the belt and associated running structure rigid and the belt remains automatically centered by the tapered or crowned rolls 29 and 30. In the event of breakage of the belt or in the event the belt is to be changed, the mechanical connector 35 is easily removed and parts of the belt operating mechanism do not have to be assembled. The belt is driven by the hydraulic motor 36 which is controllable through a main control valve.

Thus it will be seen that We have provided an improved street sweeping machine with a conveying mechanism which meets the objectives and advantages hereinbefore set forth. The mechanism is extremely reliable in operation and is improved in its function of elevating the dirt up into the hopper and in reliability and ease of servicing.

The drawings and specification present a detailed disclosure of the preferred embodiments of the invention, and it is to be understood that the invention is not limited to the specific forms disclosed, but covers all modifications, changes and alternative constructions and methods falling within the scope of the principles taught by the invention.

We claim as our invention:

1. In a street sweeping machine, a rotary cylindrical broom supported horizontally on the machine, means for driving the broom in rotation, a hopper on the machine for receiving dirt and foreign materials swept from a street surface by the broom, an elevating conveyer positioned ahead of the broom and extending to said hopper, a conveyer frame rigidly supporting said conveyer, means for lifting said frame, a pair of side shoes supported at the side of said conveyer frame to extend beside the ends of said rotary broom and having longitudinal street engaging lower edges for slidingly engaging the street surface, pivotal arms mounted intermediate their ends on each side of the frame for supporting the shoes and having a trailing end extending rearwardly toward said broom and having a forward end, a pivotal connection connected to said arm at the trailing end thereof and connected to the shoes permitting free pivotal movement of the shoes on the arms so that the shoes will be drawn forwardly by the arms and the shoes may pivot freely to slide over obstacles, and a stop member on the frame above the forward end of each of the arms positioned so that the forward ends of the arms will engage the stop members when the frame has been partially lifted to stop pivotal movement of the arms and thereby lift the shoes.

2. In a street sweeping machine, a rotary cylindrical broom supported horizontally on the machine, means for driving the broom in rotation, a hopper on the machine for receiving dirt and foreign materials swept from a street surface by the broom, an elevating conveyer positioned ahead of the broom and extending to said hopper, a conveyer frame rigidly supporting said conveyer, means for lifting said frame, a pair of side shoes supported at the side of said conveyer frame to extend beside the ends of said rotary broom and having longitudinal street engaging lower edges for slidingly engaging the street surface, pivotal arms mounted intermediate their ends on each side of the frame for supporting the shoes and having a trailing end extending rearwardly toward said broom and having a forward end, a pivotal connection connected to said arms at the trailing end thereof and connected to the shoes permitting free unlimited pivotal movement of the shoes on the arms so that the shoes will be drawn forwardly by the arms and the shoes may pivot freely to slide over obstacles, a stop member on the frame above the forward end of each of the arms positioned so that the forward ends of the arms will engage the stop members when the frame has been partially lifted to stop pivotal movement of the arms and thereby lift the shoes, and a spring connected between the for ward end of the shoe and the arm preventing the shoe from pivoting forwardly when it is lifted on the arm free of a street surface.

3. In a street sweeping machine, a rotary cylindrical broom supported horizontally on the machine on a horizontal shaft with the ends projecting from the broom, means for driving the broom in rotation, a hopper on the machine for receiving dirt and foreign materials swept from a street surface by the broom, an elevating conveyer positioned ahead of the broom and extending to said hopper, a conveyer frame rigidly supporting said conveyer, means for lifting said frame, a pair of side shoes supported at the side of said conveyer frame to extend beside the ends of said rotary broom and having longitudinal street engaging lower edges for slidingly engaging the street surface, pivotal arms mounted intermediate their ends on each side of the frame for supporting the shoes and having a trailing end extending rearwardly toward said broom and having a forward end, a pivotal connection connected to said arms at the trailing end thereof and connected to the shoes permitting unlimited free pivotal movement of the shoes on the arms so that the shoes will be drawn forwardly by the arms and the shoes may pivot freely to slide over obstacles, a stop member on the frame above the forward end of each of the arms positioned so that the forward ends of the arms will engage the stop members when the frame has been partially lifted to stop pivotal movement of the arms and thereby lift the shoes, and an elongated upwardly facing slot in the top of each of the shoes positioned to receive the shaft ends when the shoes are lifted to permit elevating the shoes relative to the broom.

References Cited in the file of this patent UNITED STATES PATENTS 2,327,879 Farrar Aug. 24, 1943 2,488,872 Mathieu Nov. 22, 1949 2,637,055 Mott May 5, 1953 2,917,761 Burgdorif Dec. 22, 1959 

